Ionic bond is a compound made up of a meta and a non-metal eg NaCl (sodium chloride)
covalent bond is made up of two non-metals eg H2O (water)
Answer:
The correct answer is - warning system.
Explanation:
Warning systems are a type of system that could be technical or biological in nature that can help in assessing or inform about the possible danger or change in a particular setting such as ecosystem, weather, water quality, and many others. It helps in avoiding such threats before occurring or become serious threats.
Certain biological species that live or require a particular set of conditions for their survival and reproduction can act as a biological warning system for water pollution, air pollution.
Active transport is a cellular transport mechanism. It’s the movement of molecules that are assisted by enzymes along the way to a higher concentration.
A biological theory, like the theory of evolution, that is widely accepted and supported by so many observations and experiments may be referred to as a principle or a law.
<h3>What is a Law?</h3>
This refers to statements which describes or predict a range of natural phenomena as a result of repeated experiments which has been performed and the authenticity has been prove by peers and other individuals.
A law is also referred to as principle and has been observed to be always true unlike due to the repeated scientific methods being done approving of its validity thereby making law the correct choice.
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